1. Field of the Invention
The present invention relates to a radio communication apparatus, a radio network system, and a data link construction method used for the same. In particular, it relates to a method of constructing a data link in a three-dimensional mesh network that interconnects communication nodes widely distributed and communication nodes on flying objects without using satellite communication, which involves a significant transmission delay time.
2. Description of the Related Art
In the mesh network described above, communication nodes are interconnected by radio line-of-sight (LOS) communication if there is no obstacle in the radio transmission channel therebetween (see Japanese Patent Laid-Open Nos. 2001-257637 and 2002-135268, for example), and communication nodes are interconnected by radio over-the-horizon (OH) communication (which is a communication method relying on tropospheric scattering) if there is an obstacle in the radio transmission channel therebetween (see Japanese Patent Laid-Open Nos. 05-292084 and 2002-164798, for example).
The mesh network described above also uses aerial-vehicle (AV) communication for communication with communication nodes on flying objects (see Japanese Patent No. 3841526, for example).
In the LOS communication, an automatic equalization processing is performed to automatically correct propagation distortion to improve communication quality. In the OH communication, an automatic diversity equalization processing is performed to automatically correct phasing and propagation distortion to improve communication quality. In the AV communication, a moving-object-tracking communication processing is performed to track a moving flying object to maintain communication.